Cosmetic methods and compositions for conditioning human skin by topical application to the skin of cosmetic compositions containing phosphates and/or sulfates of branched alcohols and/or ethoxylates thereof.
Sebum is skin oil which is produced by sebocytes (cells of the sebaceous glands in the skin) and is then secreted to the skin surface. A frequent and undesirable skin condition is xe2x80x9coily skin,xe2x80x9d the condition which results from the excessive amount of sebum on the skin. Oily skin is associated with a shiny, undesirable appearance and a disagreeable tactile sensation and affects various age groups. Therefore, cosmetic products which provide both sebum control and anti-aging benefits are highly desirable.
The prior art discloses branched alcohols as compounds which provide skin benefits such as sebum suppression. For example, U.S. Pat. No. 5,756,109 issued to Burger et al. (hereinafter xe2x80x9cBurger ""109xe2x80x9d) teaches the use of a noncylic polyunsaturated diterpene alcohol, geranyl geraniol, in combination with a retinol as a skin conditioning composition. Burger ""109 discloses sebum suppression as one advantage of the branched alcohol in combination with retinol. U.S. Pat. No. 5,344,850 issued to Hata et al. discloses topical compositions containing C18 saturated or unsaturated alcohol with four methyl branches for treating or preventing acne.
A problem exists in that branched alcohols alone inherently possess an unpleasant odor, characteristic of vinyl or a xe2x80x9cnew car smell,xe2x80x9d making application in cosmetic skin conditioning compositions highly undesirable. Moreover, branched alcohols themselves are water-insoluble.
Derivatives of branched alcohols have also been disclosed in the prior art for a variety of uses, such as personal cleansing compositions. For example, WO 9918928 assigned to The Proctor and Gamble Company, discloses personal cleansing compositions comprising branched surfactant systems having a hydrophobic group and a hydrophilic group. The hydrophobic group comprises mid-chain branched and linear surfactant compounds. The hydrophilic group is selected from the group consisting of sulfate and/or ethoxylates thereof.
U.S. Pat. No. 6,020,303 issued to Cripe et al. (hereinafter xe2x80x9cCripe ""303xe2x80x9d) discloses detergent surfactant compositions derived from mid-chain branched primary alkyl hydrophobic groups and hydrophilic groups. Specifically, Cripe ""303 discloses alkyl sulfates for application in laundry and cleaning compositions.
U.S. Pat. No. 5,093,112 issued to Birtwistle et al. discloses topical cleansing (detergent) compositions containing an alcohol and an alkyl or alkenyl phosphate salt.
U.S. Pat. No. 3,992,443 issued to Springmann (hereinafter xe2x80x9cSpringmann ""443xe2x80x9d) discloses a process for the carboxymethylation of alcohols or ether alcohols in a single stage. Springmann ""443 teaches the use of both straight chain and branched alcohols as suitable starting alcohols.
The prior art cited above does not seem to suggest or disclose cosmetic compositions or methods for skin conditioning which avoid the negative characteristics of branched alcohols. Therefore, a need remains for cosmetic compositions that retain the beneficial effects of branched alcohols in relation to sebum suppression and skin conditioning while avoiding the unpleasant odor and water-insolubility associated with such alcohols.
The present invention includes a skin care cosmetic composition comprising:
(i) from about 0.001% to about 50% of a compound of the formula A:
Rxe2x80x94Oxe2x80x94M (A) 
wherein:
R is a branched alkyl chain having at least 9 carbon atoms, generally from 9 to 15 atoms, and at least two branches;
O is an oxygen atom; and
M is (xe2x80x94SO3X), (xe2x80x94(CH2CH2O)nxe2x80x94SO3X), (xe2x80x94PO3X), or (xe2x80x94(CH2CH2O)nxe2x80x94PO3X), and mixtures thereof, where n is an integer of at least 1 and X is hydrogen or a cation;
(ii) a retinoid; and
(iii) a cosmetically acceptable vehicle.
The present invention also includes a cosmetic method of controlling or preventing an oily skin condition, especially in the facial area, by applying to the skin the inventive composition.
The invention also includes a cosmetic method of reducing, preventing or controlling sebum secretion from sebocytes by applying the inventive composition.
The invention also includes a cosmetic method of stimulating collagen synthesis by fibroblasts in the skin, by applying to the skin the inventive composition. The inventive methods and compositions provide control of sebum secretion from sebocytes, improved oil control and improved skin feel, and prevent shine and stickiness, while also providing anti-aging benefits which results in reduced appearance of wrinkles and aged skin, improved skin color, treatment of photoaged skin, improvement in skin""s radiance and clarity and finish, and an overall healthy and youthful appearance of the skin.